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A130372
Signature permutation of a Catalan automorphism: apply *A074686 to the last subtree, if the root degree (A057515(n)) is odd.
4
0, 1, 2, 3, 4, 5, 6, 8, 7, 9, 10, 11, 12, 13, 14, 15, 16, 22, 21, 19, 17, 18, 20, 23, 24, 25, 27, 26, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 64, 63, 47, 58, 59, 62, 51, 52, 53, 46, 45, 56, 48, 49, 50, 60, 54, 55, 57, 61, 65, 66, 67, 68, 69, 70, 71
OFFSET
0,3
PROG
(Destructive Scheme implementation of this automorphism, which acts on S-expressions, i.e. list-structures:)
(define (*A130372! s) (if (odd? (length s)) (*A074686! (car (last-pair s)))) s)
CROSSREFS
Inverse: A130371. a(n) = A074686(A130369(n)) = A074686(A130376(A074685(n))) = A130370(A130376(A130369(n))).
Sequence in context: A100708 A222252 A130371 * A353825 A353824 A089865
KEYWORD
nonn
AUTHOR
Antti Karttunen, Jun 05 2007
STATUS
approved